---
id: "CVE-2026-115455"
kind: "vulnerability"
aliases: ["CVE-2026-115455"]
title: "GCC libstdc++: bitset wide-stream extraction overflows stack, crashes application"
severity: "medium"
cvss: 6.5
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["c++", "gcc", "libstdc++", "runtime"]
not_affected_if: ["no-untrusted-input", "no-wide-stream-bitset"]
published_at: "2026-10-30T08:16:55+00:00"
first_seen_at: "2026-10-30T08:29:26+00:00"
updated_at: "2026-10-30T08:30:22+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-115455", "first_seen_at": "2026-10-30T08:29:26+00:00"}]
---

# GCC libstdc++: bitset wide-stream extraction overflows stack, crashes application

In GCC's libstdc++, extracting data into a bitset from a wide-character stream allocates stack memory without correctly accounting for character size and alignment. Crafted input can cause a stack-based buffer overflow, which an attacker can use to crash the application (denial of service).

_Summary, check and fix written by a model from the sources; labelled as such._

## Timeline

- 2026-10-30T08:29:26+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-115455

## From the sources

A flaw was found in GCC libstdc++. When an application extracts data into a bitset from a wide-character stream, internal stack memory allocation fails to properly account for character size and alignment. An attacker capable of supplying crafted input to an affected application could trigger a stack-based buffer overflow leading denial of service (DoS).

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